Methods for killing plant fungi



United States Patent Ofiice 3,274,051 Patented Sept. 20, 1966 3,274,051METHODS FOR KILLING PLANT FUNGI Masaru Kado, Takeo Tsuboi, and TaizoMaeda, Shimizu, and Eiichi Yoshinaga, Ogasa-gun, Japan, assignors toIhara Chemicals Company Limited, Shimizu, Japan, a

corporation of Japan No Drawing. Filed July 27, 1964, Ser. No. 385,489

Claims priority, application Japan, Aug. 30, 1963, 38/45,411; Feb. 5,1964, 39/5,692 1 Claim. (Cl. 16730) This invention relates to afungicidal composition for agricultural and horticultural purposes forpreventing plant diseases, such as rice blast (Piriculariu oryzae), andsheath blight (Pellicularia sasakii) by applying it to the place wherethe growth of disease is anticipated, and preventing its growthpreviously or destroying therapeutically by applying it to the placewhere the disease had occurred.

For preventing the rice blast (Piricularia oryzne), sheath blight(Pelliculnria sasakii) which are main diseases of paddy field rice plantseveral kinds of organo mercuric fungicides mainly phenyl mercuricacetate and organo arsenic fungicide respectively have heretofore beenused. Such known fungicides, however, contain metal or metals of metalcompound which remains in hull after the fungicide was dispersed so thatit may be harmful to the health of people taking rice as normal food.

The compositions of the invention, however, do not contain metal so thatthere is absolutely no danger of causing chronic poison to human bodyand moreover, have exceedingly excellent fungicidal activity.

The compounds constituting the active ingredient of the fungicidalcomposition of the invention are exemplified as follows:

( 1) S-benzyl-0.0diethylthiolophosphate (2) S- (o-chlorobenzyl)0.0-diethylthiolophosphate (3)S-(o-bromobenzyl)0.0-diethylthiolophosphate 4) S-(m-bromobenzyl)0.0-diethylthiolophosph ate (5 S- (p-chlorobenzyl)0.0-diethylathiolophosphate (6) S- 3,4-dichl0r:obenzyl)OO-dirnethylthiolophosphate (7) S- 3,4-dichlorobenzyl)0.0-diethylthiolophosphate (8) S-(2,6-dichlorobenzy1)0.0-diethylthiolophosphate (9)S-(pbromobenzyl)0.0-diethylthiolophosphate 10) S-(3,4-dibromobenzyl)0.0-diethylthiolophosphate l 1 S-benzyl-0.0-dimethyldithioplrosphate(12) S- (p-chlorobenzyl) 0.0-dimethyldithiophosphate (13)S-(m-nitrobenzyl) 0.0-dimethyldithiophosphate 14) S- (p-nitrobenzyl)0.0-dimethyldithiophosphate (15 S-benzyl-0.0-diethyldithiophosphate 16)S-(-o-chlorobenzyl) 0.0-diethyldithiophosphate l 7) S- m-chlorobenzyl)0.0-diethyldithiophosphate (18) S- (p-chlorobenzyl)0.0-diethyldithiophosphate 19) S-( 3,4-dichlorobenzyl)0.0-diethyldithiophosphate (20) S-(2,6-dichlorobenzyl)0.0-diethy-ldithiophosphate (21 S-(o-nitrobenzyl)0.0-diethyldithiophosphate (22)S-(m-nitrobenzyl)0.0-diethyldithiophosphate (23) S- (p-nitrobenzyl)0.0-diethyldithiophosphate (24) S-(4-bromoZ-nitrobenzyl)0.0-diethylthiolophosphate (25) S-(4-bro-mo3-nitrobenzyl)0.0-ldiethylthiolophosphate (26) S-(4-chloroZ-nitrobenzyl)0.0-diethyldithiophosphate (27) S-(4-chloro-2-nitnobenzyl) OlO-dimethyldithiophosphate (28) S-(4-nitro2-chlorobenzyl)0.0-diethyldithiophosphate (29) S-(4-chloro2-nitrobenzyl)0.0diethylthiolophosphate (30) S-(4-chloro3-nitrobenzyl)0.0-diethylthiolophosphate The fungicidal compositions foragricultural and horticultural purposes according to the invention mayhave the form of dust, wettable powder or emulsifier concentrate and maybe manufactured by the following methods respectively and obtained as amixture with carrier.

The carrier in the specification means a carrying or hearing body to heused for carrying active ingredient to a desired place and may be ofsolid or liquid, that is, the solid carriers are fine powders of clay,pyrophyllite, talc, diatomaceous earth, silica, vermiculite, calciumcarbonate, are mixed with the active ingredient of the invention andcrushed into dust. Further wett-able spreader and surfactant such assodium lignin sulfonate, sodium dinaphthyl methane disulfonate orcorresponding ammonium salts or calcium salts, octylphenyl polyoxyethylether and the like alkyl polyoxy ether may be added and the mixture iscrushed to provide wettahle powder.

Liquid carrier are solvents for the active ingredient of the inventionand non-solvent which can disperse or .dissolve active ingredient bymeans of an auxiliary agent, for instance, water, benzene, kerosene,alcohol, acetone, methyl naphthalene, cyclohexanone, animal andvegetable oils and aliphatic ester and surfactants and the like liquidcarrier may be mixed and stirred to manufacture an emulsifier.

In using the compositions of the invention, in case of powder material,it can be directly dusted on the leaves or stems of plants, and in caseof emulsifier concentrate, it can be diluted with water etc. to asuit-able concentration and may be applied on leaves and stems of plantsby spraying it with a sprayer and in case of wettable powders they canbe applied by spraying as a suspension of a suitable concentration withwater.

It is of course desirable to expect positive elfect by mixing surfactantsuch as spreader, emulsifier, wettable spreader, sticker which areusually used as an auxiliary agent for spreading the fungicide.Moreover, the fungicides of the invention may be used in mixture withinsecti cide, such as, BHC, parathion, fungicides such as various kindsof organo sulfur compounds, copper compounds, mercuric compounds orplant growth regulants, such as 24-D or fertilizers.

The method "of manufacturing the compositions of the invention and alsothe manner of using the same will be explained in the followingexamples:

It should be noted that the additives and active ingredients may bechanged over a wide range.

Example 1.Method of manufacturing dusts and manner of using same Amixture of 2% of S-(3,4-dichlorobenzyl)0.0-diethy1- thiolophosphate and98% of diatomaceous earth-Dicrite (trademark of Dicrite Kagaku KogyoCo., Ltd., kaolin system) was pulverized to manufacture the dusts.

The powder may be directly dusted by means of a duster on the spotswhere rice 'blast (Piricularia oryzae) or sheath blight (Pelliculariasasakii) have been infected to destroy the disease.

Example 2.Meth0d of manufacturing dusts and manner of using same Amixture of 5% of S-benzyl-0.0-dimethylthiolophosphate and 95% ofdiatomaceous earth, pyrophyllite mixture was pulverized to make the dustand it was used in the same manner as in Example 1.

Example 3.-Meth0d of manufacturing wettable powder and manner on its useA mixture of 15% of S-(p-chlorobenzyl)0.0-diethylthiolophosphate, ofdiatomaceous earth--ka0lin mixture and 5% of spreaderEmale (trademark ofKao Soap (30., Ltd.) was pulverized to make the wettable powder.

In case of using the wettable powder was suspended in water and sprayedon the leaves and stems of paddy field rice plant infected by rice blast(Piricularia oryzae) to destroy the disease.

Example 4.--Methd of manufacturing emulsion type wettable powder and itsuse 15% of S- (p-nitrobenzyl) 0.0-dimethyldithioph0sphate and ofemulsifier, Solpole (trademark of Toho Kagaku Kogyo Co., Ltd.) weremixed and dissolved, then the mixture was adsorped by 80% ofdiato-maceous earth Dicrite (trademark of Dicrite Kakaku Kogyo Co.,Ltd., kaolin system). In case of using it was diluted with water to asuitable concentration and sprayed as suspension liquid. I

Example 5.--Meth0d of manufacturing emulsifier and its use 80% ofS-(o-nitrobenzyl)0.0-diethyldithiophosphate and 20% of emulsifierSolpole (trademark of Toho Kagaku Kogyo Co., Ltd.) were mixed anddissolved to make an emulsifier concentrate. It was diluted with waterto be used as spraying liquid.

Example 6.Meth0d of manufacturing emulsifier concenpurposes according tothe invention against the pathogenic organism.

(a) Antiamicrobial spectrum by the agar dilution method (Misatosmodified met/10d ).Aqueous dilution liquid of the composition of theinvention in the formulation of emulsifier was mixed to the agarcultivation group and flowed into a Petri dish of 9 cm. in diameter tosolidify to make the concentrations of the effective ingredients 1, 10and 100 p.p.m. To each of the agars was inoculated pathogenic organismsand left for 3 days at 28 C., then the growths of the fungi wasinspected and the concentration the compounds for preventing of thegrowth of the test organisms was expressed in p.p.m. unit.

(b) Inspection of spore germination LD90 by Petri dish pr0cess.Adefinite quantity of acetone solution of each medicine was dropped in asmall Petri dish (inner diameter of 4.2 cm.) and the solvent was driedout at room temperature.

After drying, for the sake of accelerating the germination of spore 5ml. of Hopkins nourishing liquid and 1 ml. of suspension liquid havingfungi spore of rice blast (Piricularia oryzae) were added and after thespores were uniformly distributed in the Petri dish it was placed in athermostatic container at 28 C. and left for 24 hours, then tested by amicroscope.

The active ingredient g/cm?) showing 90% suppressing rate of sporegermination was settled as LD-90 of active ingredient.

Agar dilution method (p.p.m.) H

Name of active ingredient A B C D E F G LD-90 1 (us-lS-benzyLO.-O-diethylthiolophosphate 100 100 100 10 100 100 100 5. 0S-(o-chlorobenzyl) O .O-diethylthiolophosphate 100 10 100 10 100 100 1008. 1 S-(p-chlorobenzyl)0.0-diethylthiolophosphate 10 10 100 10 100 100100 7. 5 S-(3, 4-dichlorobenzyl) 0.0-diethylthiolophosphate 10 10 100 10100 100 100 3. 7 S-(trbrombenzyl) O .0-(1iethylthiol0- phosphate 10 10100 10 100 100 100 8. 7 S-benzyl-O .O-dirnethyldithiophosphatm 10 10 10010 100 100 100 2. 0 S-(p-ehlorobenzyl) O.O-di1nethyldithiophosphate 10010 100 10 100 100 100 3. 2 S-(p-nitrobenzyl) O.O-dirnethyldithiophosphate 10 10 100 10 100 100 100 3. 3S-benzyl-0.0-diethyl(1ithiophosphate. 10 10 100 10 10 100 100 l. 3S-(m-ehlorobenzyl) O .O-diethyldithiophosphate 10 10 100 l 10 100 100 0.9O S-(p-chlorobenzyl) 0.0-diethyldithiophosphate 10 10 100 1 10 100100 1. 1 S-(2, G-diehlorobenzyl) O .O-diethyldithiophosphate 10 10 10 110 100 100 1.3 S-(o-nitrobenzyl)-O .Odiethyldithiophosphate. 10 10 10 110 100 100 0. 37 S-(m-nitrobenzyl))0.0-diethyldithiophosphate 10 10 10 110 100 100 0. 95 S-(4-ehl0r0-2-nitr0b8nzyl) O dithiophosphate 10 1O 1O 110 10 10 1. 3 S-(4-nitro-2-ehlor0ben phosphate- 100 100 100 100 100 100100 7. 3 S-(4-chlor0-2Fn phosphate- 100 100 100 10 100 100 100 3. 7 S(4-bromo-3- l) O .O-diethylthiolophosphate 10 10 10 10 100 10 1O 2. 8Zineb (Trademark of Rohm and Haas 00.)

(Standard medicine) 100 10 100 10 100 100 100 0. 72

therein to produce the emulsifier concentrate. The emulsifierconcentrate was diluted with water to emulsion and .used as a sprayingliquid.

The results of fungicidal tests of the compositions according to theinvention for various kinds of pathogenic fungicidal compositions foragricultural and horticultural 1 The active ingredient g/em. ofsuppressing rate of spore germination.

: Helminthosporlum leaf spot (Cochliobolus miyabe anus). Melanose(Phomopnst's citri).

: Anthraenose (Gloeosporium Zaeticolol).

: Rice blast (Pirieularia oryzae).

: Black spot (Alternaria. ktkuchiana),

: Fusarium wilt (Fusarium omysporium f. Moment).

2 Bacterial leaf blight (Xanthomonas org we).

: Rice blast (Pt'ricularia orye'ae),

Experimental Example 2 Determination of activity of inhibition toinfection of sheath blight ('Pellicularia sasakii) to paddy rfield riceplant.

First young leaf of cowpea was immersed into a liquid of the compositionof the invention in the form of emulsifier diluted with water and aftertreated thereby it was air dried. Fungi series of sheath blight(Pellicularia sasakii) previously cultivated on a plane medium waspunched together with agar by a cork holer of 7 mm. in diameter andmaintained in thermostatic container at 2 8 C. for 2 days placinginoculation source. By examining infected area the inhibition value wascalculated.

Name of active ingredient A B (lg) p.p.m ercent)S-(oehlorohenzyl)0.0-diethy1- 150 1, 000 89 thiolophosphate 300 500 62S-(3,4-diehlrobenzyl) O. O-diethyl- 150 1, 000 7 thiolophosphate 300 50010 S-(p-bromobenzyl) O .O-diethyl- 150 1, 000 86 thiolophosphate 300 50072 S-(3,4-dibrom0benzyl) O. O-diethyl- 150 1, 000 82 thiolophosphate 300500 70 S-(2,6-dichlor0henzyl) 0.0-diethyl- 150 1, 000 92 thiolophosphate300 500 78 S-(pnitrobenzyDQO-dimethyl- 150 1, 000 82 dithiophosphate 300500 68 S-(p-ehloroloenzyl) 0.0-diethyl- 150 1, 000 90 dithiophosphate300 500 82 S-(3,4-dichl0r0benzyl) 0.0-diethyl- 150 l, 000 95dithiophosphate 300 500 90 S-(m-nitrobenzyl) 0.0-diethyl- 150 1, 000 100dithiophosphate 300 500 87 S-(p-nitrobenzyl) O. O-diethyl- 150 l, 000100 dithiophosphate 300 500 87 S-(4eh1or0-2-nitrobenzyl) O.O-d1ethyl-150 1, 000 82 dithiophosphate 300 500 G0 Ferric methyl arsonate(Standard 200 97 medicine) 100 82 NOTE.

A Dilution rate. B Concentration of effective ingredient. C Inhibitionvalue. Experimental Example 3.Test for destroying rice blast(Piricularia oryzae) by emulsifier concentrate Paddy field rice plant(species, Aichi asahi) was directly seeded and planted and at its threeleaves period the composition of the invention in the form of emulsifiersame as that manufactured in the same manner as in Example was dilutedwith water and sprayed on the leaves and on the next day a liquidsuspended with spores of fungi of rice blast (Piricularia oryzae) takenfrom the diseased leaves was inoculated by spraying. After one Week ofthe inoculation the number of diseased spots on the main leaf (the thirdleaf) were examined.

Name of active ingredient A B C p.p.m.

S-(rfichlorobenzyl)0.0-diethylthiolophos- 150 1 000 23 p ate S-(3,4-'chlorobenzyl)0.0-dirnethylthiolo- 300 500 55 phosphate 150 1, 000 45S-(p-btromobenzyl)0.0-d1ethy1th1olophos- 1 pha es-(iie-dgbromobenzyl)0.0-diethylthiol0phes- 1 p ate .1S-(rg-bromobenzyl)0.0-diethylthiolophos- 1 p ateS-(p-nitrobenzyl)0.0-dimethyldithi0phos- 1 p rateS-(m-chlorobenzyl)0.0-diethyldithiophos- 1 5% phateS-(3fi4-dichlorobenzyl)0.0-diethyldithioph0s- 1 I? p ates-(rlrll-nitrobenzybo.O-diethyldithiophos- 1 1g p ateS-(4-ehloro-2nitrobcnzyl) 0.0-dimethyl 300 500 5 dithiophosphate 150 1,000 22 S-(l-ehl0ro-2-nitr0henz yl) 0.0-dlethylth1ol0- 300 500 3:;phosphate 1 3g ggg N ondispersion 215 N ore-- A: Dilution rate. B:Concentration. C: Number of diseased spot per leaves (average).

Experimental Example 4.T est for destroying rice blast (Piriculariaoryzae) Paddy field rice plant (species, Aichi a'sahi) was directlyseeded and cultivated and at its three leaves period the composition ofthe invention in the form of dust same as that manufactured in the samemanner as in Example 1 was dusted on the leaves. On the next day, aliquid suspended with spores of fungi of rice blast (Piricularia oryzae)taken from the infected leaves was inoculated by spraying. After oneweek of the inoculation the number of diseased spots on the main leaf(the third leaf) were examined.

Name of active ingredient B (percent) N OTE.-

B: Concentration. 0: Number of diseased spots per average 10 leaves.Experimental Example 5.Test of destroying rice blast (Piriculariaoryzae) by wettable powder fungicide Paddy field rice plant (species,Aichi asahi) was directly seeded and cultivated and its three leavesperiod the composition of the invention in the form of wettable powdersame as that manufactured in Example 3 suspended in water was sprayed onthe leaves by means of a sprayer.

On the next day, a liquid suspended with spore of fungi of rice blast(Piricularia oryzae) taken from the diseased leaves was inoculated byspraying. After one Week of the inoculation the number of diseased spotson the main leaf (the third leaf) were examined.

Name of active ingredient A B S-(p-ehlorobenzyl)0.0-diethylthio1o- 1,000 21 phosphate 300 500 42 S-(3,4-diehlorobenzyl) 0.0-dimethylthil0-150 1, 000 42 phosphate 300 500 65 S-(o-ehlorobenzyl)0.0-dimethylthio1o- 150 1, 000 25 phosphate 300 500 31S'(3,4-dichlorobenzyl) O .O-diethylthiolo- 150 1, 000 21 phosphate 300500 29 S-(4-chloro-2-nitrobenxyl) O. O-diethylthiolo- 150 l, 000 31phosphate 300 500 48 S-(o-ehlorobenzyl) 0.0-diethyldithio- 15C! 1, 00026 phosphate 300 500 39 N0n-dispersi0n 215 NOTE.

A: Dilution rate. B: Concentration. C: Number of diseased spots peraverage 10 leaves.

What we claim is: Method of killing plant fungi comprising applyingthereto S-benzyl-OJO-diethylthiolophosphate.

References Cited by the Examiner UNITED STATES PATENTS 1,589,675'3/195'2 Cook et al. 26'O46=1.112 2,609,383 9/1952 Craig 2 6 O- 46 L1122,862,017 11/1958 Sohrader et al. 260-46111 12 3,156,718 11/1964 Lorenzet al. 2 60461 LEWIS GOTTS, Primary Examiner. SH'EP K. ROSE, AssistantExaminer.

